TECHNICAL REPORT ON CONE PENETRATION, PLASTIC LIMIT AND PLASTICITY INDEX TEST PROFICIENCY 2015 CETANZ Technical Report TR 6 Author(s) J. Ellis Report Date First Issue 13 November 2015 Report Revision Date - Revision Number 1 Associated Test Method(s) NZS4407:1991 3.2, 3.3 & 3.4
NZS4407:1991 3.2, 3.3 & 3.4 Page 2 of 7 CONE PENETRATION, PLASTIC LIMIT & PLASTICITY INDEX PROFICIENCY 13/11/15 CONE PENETRATION, PLASTIC LIMIT AND PLASTICITY INDEX TEST PROFICIENCY 2015 1. Introduction In 2015, CETANZ organised and ran an inter-laboratory proficiency scheme on the, and ity tests, designed to achieve the following outcomes: 1. Provide results that should enable participants to improve their performance. 2. Provide information relevant for calculation of uncertainty. 3. Identify problems with, or between, laboratories. 4. Potentially identify needs for test method improvement. The following Laboratories participated in the scheme: Central Testing Services - Alexandra Coffey Geotechnics NZ Ltd Downer Auckland Laboratory Downer Christchurch Laboratory Fulton Hogan Laboratory - Auckland Fulton Hogan Laboratory - Canterbury Fulton Hogan Laboratory - Waikato Envirolab Geotest Ltd Higgins - Palmerston North Holcim Bombay OPUS International Consultants - Auckland OPUS International Consultants - Christchurch OPUS International Consultants - Gisborne OPUS International Consultants - New Plymouth OPUS Research OPUS International Consultants - Rotorua OPUS International Consultants - Tauranga OPUS International Consultants - Wanganui OPUS International Consultants - Whangarei Test Lab - Wanganui Winstone Aggregate Ltd - Auckland Laboratory Winstone Aggregate Ltd - Wellington Laboratory Stevenson Laboratory To ensure anonymity of results each laboratory was assigned a unique identifier by Keith Towl of IANZ. All participating Laboratories returned results. CETANZ TR6 CONE PENETRATION, PLASTIC LIMIT, PLASTICITY INDEX PROFICIENCY 2015
NZS4407:1991 3.2, 3.3 & 3.4 Page 3 of 7 CONE PENETRATION, PLASTIC LIMIT & PLASTICITY INDEX PROFICIENCY 13/11/15 2. Sample Preparation & Instruction Each Laboratory was sent two aggregate test samples of approximately 8kg each, enough for a technician to complete one, and ity test on each sample. Each Laboratory was given the option to request additional samples for additional technicians or Uncertainty of Measurement calculations. The samples supplied were: -PAP 6 material from Stevenson Drury Quarry -GAP20 material from Stevenson Huntly Quarry Bulk field samples were taken from the respective quarries and split down by Stevenson Laboratory to provide test samples. The test samples were labelled A (PAP 6) and B (GAP 20). Laboratories were instructed to carry out preparation and testing as per NZS 4407:1991: test methods 3.2, 3.3 & 3.4 and to ensure all testing was carried out on the fraction passing the 425µm test sieve. All Laboratories were instructed to ensure that only technicians that were deemed proficient were to complete the testing. CETANZ TR6 CONE PENETRATION, PLASTIC LIMIT, PLASTICITY INDEX PROFICIENCY 2015
3. Results Laboratory I.D. Balance Used Water Reduction Method Water Used IANZ Accredited Equilibration Period (Operator A) Sample A ity (Operator B) Sample A ity (Operator A) Sample B ity (Operator B) Sample B ity nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp nearest 0.1dp 1 0.01g Filtration Tap Yes 24hrs min 21.4 NP NP 34.6 21.0 13.6 2 0.01g Filtration Distilled Yes * 19.7 14.7 5.0 19.6 NP NP 32.9 15.3 17.6 32.6 18.5 14.1 3 0.001g Filtration Distilled Yes 24hrs min 20.1 17.2 2.9 20.2 15.3 4.9 32.6 19.1 13.5 32.0 16.4 15.6 4 0.001g Evaporation & Filtration Distilled Yes 7 days 21.3 NP NP 34.4 19.6 14.8 CETANZ: 5 0.001g Evaporation Distilled Yes 16hrs min 20.2 NP NP 32.3 17.5 14.8 Operator A - 19+ hrs Slp A 6 0.0001g Filtration Tap Yes 24hrs min 20.2 NP NP Operator A - 24+ Hrs Spl B 32.0 17.9 14.1 7 0.001g Evaporation Distilled Not Reported 24hrs min 19.7 NP NP Operator B - 16 min hrs Spl A & B 31.2 17.1 14.1 8 0.0001g Evaporation Distilled Yes 24hrs min 19.1 NP NP 32.5 18.2 14.3 9 0.001g Evaporation Tap Yes 16hrs min 25.0 17.4 7.6 32.2 17.0 15.2 10 0.001g Evaporation Distilled Yes 24hrs min 21.2 NP NP 34.0 16.3 17.7 11 0.0001g Evaporation & Filtration Tap Yes 24hrs min 20.7 NP NP 21.4 NP NP 32.5 17.9 14.6 32.7 17.9 14.8 12 0.001g Evaporation & Filtration Distilled Yes 24hrs min 20.6 17.9 2.7 32.8 19.1 13.7 13 0.001g Evaporation Tap Yes Not Reported 21.2 3.3 17.9 34.7 19.9 14.8 14 0.001g Evaporation Tap Yes 24hrs min 21.3 NP NP 21.5 NP NP 35.4 20.7 14.7 33.5 19.8 13.7 15 0.001g Evaporation & Filtration Tap Yes 24hrs min 19.6 NP NP 31.8 18.5 13.3 16 0.001g Evaporation & Filtration Tap Yes 24hrs min 20.3 NP NP 32.0 20.2 11.8 17 0.0001g Evaporation Distilled Yes 12hrs min 25.6 19.4 6.2 23.2 17.7 5.5 36.8 25.0 11.8 36.2 20.5 15.7 18 0.01g Evaporation Distilled No 24hrs min 19.3 NP NP 31.6 18.4 13.2 CETANZ: CETANZ: 19 0.001g Evaporation Tap Yes 24hrs min 20.2 NP NP 31.7 17.8 13.9 Operator B - Distilled Operator B - Distilled 20 0.001g Evaporation Tap Yes 24hrs min 19.5 NP NP 30.4 16.6 13.8 21 0.001g Evaporation Tap Not Reported 24hrs min 19.6 NP NP 19.3 NP NP 30.8 18.0 12.8 29.9 17.8 12.1 22 0.001g Evaporation Deionised Yes 24hrs min 20.7 14.3 6.4 34.6 17.5 17.1 23 0.001g Evaporation & Filtration Distilled No 7 days 22.0 NP NP 27.2 15.5 11.7
4. Analysis For the purpose of analysis, all results, including the duplicate test data provided by some of the participants, have been tabulated. Each participant will need to undertake their own analysis on the data provide to gauge their own performance. The graphs provided, only display result plots versus simple Average, ± 1 Standard Deviation and ± 2 Standard Deviation limits. s or ity has not been plotted for Sample A due to the test results being mostly Non and therefore impossible to graphically represent. Graph 1
Graph 2 Graph 3 Graph 4
NZS4407:1991 3.2, 3.3 & 3.4 Page 7 of 7 CONE PENETRATION, PLASTIC LIMIT & PLASTICITY INDEX PROFICIENCY 13/11/15 5. Conclusions The results seem to indicate the possibility of a relatively large amount of variation for both types of sample tested. More advanced analysis is required, but initial indications are that the variation or reproducibility could be as high as ±7 ity. Given that current ity s for premium basecourse are 5 or Non-, this data would seem to indicate that an issue exists and further work should be done. 6. Further action Advise stakeholders of proficiency data and arrange for more in-depth analysis and publication of results. 7. Referenced Documents NZS 4407:1991: Part 2 tests 3.2, 3.3 & 3.4. 8. Disclaimer The information in this publication is to encourage high standards within the civil engineering testing industry. The information is intended as a technical report for CETANZ members only and in no way purports to be a robust statistical analysis. CETANZ cannot accept any liability of any sort for unsatisfactory site or laboratory work carried out by Companies who are members of CETANZ or organisations who claim to be following this report. CETANZ assumes no responsibility for any loss which may arise from reliance on the report and disclaims all liability accordingly. Specialist and/or legal advice should always be sought on any specific problem or matter. CETANZ TR6 CONE PENETRATION, PLASTIC LIMIT, PLASTICITY INDEX PROFICIENCY 2015